"""
集合
"""
# list 有序集合
classmates = ['Michael', 'Bob', 'Tracy']
print(classmates)
print(len(classmates))
print(classmates[0])
print(classmates[-1])

classmates.append('Adam')
print(classmates)
classmates.insert(1, 'Jack')
print(classmates)

classmates.pop()
print(classmates)
classmates.pop(1)
print(classmates)

# tuple 不可变的有序集合
t = (1, 2)
print(t)
